Articles for "Question of the week"

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Energy | 07. June 2010 | posted by Jan Oliver Löfken

Energy question of the week: How does one weigh the greenhouse gas carbon dioxide?

Automotive manufacturers are now required to indicate the precise level of carbon dioxide emissions for every new car. Small, low-emission cars seldom exceed 100 grams of carbon dioxide per kilometre. Gas-guzzling luxury saloons or SUVs (large off-road vehicles or pickups for example) can emit more than three times these levels into the atmosphere. But carbon dioxide is a gas. How does one actually put a gas on a set of scales? read more

Energy | 31. May 2010 | posted by Jan Oliver Löfken | 1 Comment

Energy question of the week: Is there such a thing as free electricity?

When we pay our electricity bill, we are paying for more than just the operation of wind turbines or nuclear power stations. What with rental for the electricity meter, costs for using the power grids, value-added tax and a tax on electricity, coupled with a surcharge for the preferred sourcing of green power, the final price we pay is effectively double the generation cost. Having said that, is it conceivable that there is such a thing as free electricity in the ever more dynamic power market? read more

Energy | 25. May 2010 | posted by Jan Oliver Löfken

Energy question of the week: Can laptops and iPads dispense with power sockets in the future?

'Mobile electricity' - that is, electricity available on the move - is the most valuable form of electrical power. This is why it is worthwhile equipping notebooks and laptops with expensive lithium-ion batteries that need to be recharged at regular intervals by plugging them into power sockets. The iPad, which looks set to spur the market for electronic reader devices, remains uninteresting without its batteries. However, solar cells and hand cranks are already able to generate standalone power for mobile devices. Will these devices be able to cope entirely on their own without power sockets someday? read more

Energy | 17. May 2010 | posted by Jan Oliver Löfken | 4 Comments

Energy question of the week: How much energy is there in the Earth's interior?

Ninety-nine percent of the Earth is hotter than 1000 degrees Celsius. Inside Earth's core, temperatures rise to 7000 degrees. In total, the power within our planet amounts to thousands of billions of watts. This reservoir has its origins in the residual heat dating from the time the Earth was created, roughly 4.6 billion years ago, and in the ongoing radioactive decay of long-lived isotopes of uranium, thorium and potassium. The question we need to ask ourselves is why, given these gigantic amounts of energy, does geothermal power still only account for far less than one percent of our energy usage? read more

Energy | 10. May 2010 | posted by Jan Oliver Löfken

Energy question of the week: Can sunlight be used to split water directly into oxygen and hydrogen?

Solar cells are good at converting sunlight directly into electricity. However, they come nowhere close to the efficiency of natural photosynthesis. Using chlorophyll, green plants have mastered the art of producing energy-rich molecules such as sugar and starch from carbon dioxide, water and sunlight. Would it not make sense to harness this natural process to generate energy? read more

Energy | 26. April 2010 | posted by Jan Oliver Löfken | 3 Comments

Energy question of the week: Does the future of wind power lie in the open seas?

In January 2010, wind farms in Germany had a generating capacity of 25,777 megawatts. This means that almost eight percent of Germany's electricity requirement can be met in a climate-neutral way. However, since land areas exposed to strong winds are limited, both large and small-scale power-generating businesses are jostling for position out in the open sea. This poses a simple question: are offshore wind farms genuinely more efficient? read more

Energy | 12. April 2010 | posted by Jan Oliver Löfken

Energy question of the week: Is it possible to fly on nothing but solar power?

In cruise ships, electrical propulsion units – powered by diesel engines – are now standard equipment. Every day, buses with electric motors powered by fuel cells ply the streets of Hamburg. Now the first aircraft powered solely by electric motors are taking off. However, in the quest to find exciting, original and climate-friendly propulsion, are solar cells powerful enough to get an aircraft off the ground? read more

Energy | 06. April 2010 | posted by Jan Oliver Löfken | 2 Comments

Energy question of the week: How is electrical power carried across the sea?

Two trends are emerging for future renewable electricity. In the first, local solar, wind or biomass plants will produce more energy for small communities or single homes. In the second, large amounts of electricity will be generated by solar power stations in desert areas or extensive offshore wind farms, and delivered over long distances to densely populated areas. But how can electrical power be delivered over long distances without large losses? read more